Summary Of Significant Accounting Policies (Narrative) (Details)	1 Months Ended		3 Months Ended								12 Months Ended
	Jan. 31, 2020 USD ($)	May 31, 2016 USD ($)	Dec. 31, 2022 USD ($) shares	Sep. 30, 2022 USD ($)	Jun. 30, 2022 USD ($)	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($) loan shares	Sep. 30, 2021 USD ($)	Jun. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2022 USD ($) loan $ / shares shares	Dec. 31, 2021 USD ($) $ / shares loan shares	Dec. 31, 2020 USD ($) $ / shares shares	Dec. 31, 2023 USD ($)	Sep. 30, 2023 USD ($)	Jun. 30, 2023 USD ($)	Mar. 31, 2023 USD ($)	Oct. 26, 2022 USD ($)	Aug. 13, 2020 USD ($)	Mar. 31, 2020 USD ($)
Accounting Policies [Line Items]
Notional Amount			$ 6,800,000								$ 6,800,000
Loans held for investment			5,464,479,000				$ 3,729,418,000				5,464,479,000	$ 3,729,418,000
Other real estate owned			21,210,000				18,873,000				21,210,000	18,873,000	$ 0
Net realized and unrealized gains (losses) on commercial loans, at fair value											13,531,000	14,885,000	(3,874,000)
Provision for credit losses											7,108,000	3,110,000	6,352,000
Loans held for sale			$ 589,100,000,000				$ 1,390,000,000				589,100,000,000	1,390,000,000
Advertising costs											$ 1,200,000	$ 1,600,000	$ 1,300,000
Stock options included in dilutive earnings per share, due to exercise price per share being less than average market price | shares			480,104				450,104				480,104	450,104	1,056,604
Minimum exercisable prices (in dollars per share) | $ / shares											$ 6.87	$ 6.87	$ 6.75
Maximum exercisable prices (in dollars per share) | $ / shares											$ 18.81	$ 18.81	$ 8.57
Restricted cash and cash equivalents			$ 0				$ 0				$ 0	$ 0
Anti-dilutive shares not included in earnings per share calculation | shares											100,000	100,000	105,000
Amortization of intangible assets											$ 398,000	$ 398,000	$ 556,000
Amortization expense per year			398,000								398,000
Accumulated Amortization			2,442,000				2,044,000				2,442,000	2,044,000
Finite-Lived Intangible Assets, Gross			4,491,000				4,491,000				4,491,000	4,491,000
Stock Repurchase Program, Authorized Amount			15,000,000.0	$ 15,000,000.0	$ 15,000,000.0	$ 15,000,000.0					15,000,000.0
Cost of repurchased share			15,000,000.0	$ 15,000,000.0	$ 15,000,000.0	15,000,000.0	$ 10,000,000.0	$ 10,000,000.0	$ 10,000,000.0	$ 10,000,000.0	$ 60,000,000.0	$ 40,000,000.0
Purchase of treasury shares (in shares) | shares											2,322,256	1,835,061
Share repurchased during period, shares | shares											2,322,256
Number Of Loans Sold | loan							2					2
Long-term borrowings			10,000,000.0				$ 39,500,000				$ 10,000,000.0	$ 39,500,000
Number Of Loans Repaid | loan											1
Average cost of repurchased stock (in dollars per share) | $ / shares											$ 25.84	$ 21.80
Retained earnings			369,319,000				239,106,000				$ 369,319,000	$ 239,106,000
Deferred Tax Assets, Gross			31,237,000				35,357,000				31,237,000	35,357,000
Other liabilities			56,335,000				62,228,000				56,335,000	62,228,000
Purchase of lease receivables											$ 53,300,000
Common Stock Repurchase Program, 2023 [Member]
Accounting Policies [Line Items]
Stock Repurchase Program, Authorized Amount																		$ 100,000,000.0
Forecast [Member] | Common Stock Repurchase Program, 2023 [Member]
Accounting Policies [Line Items]
Stock Repurchase Program, Authorized Amount														$ 25,000,000.0	$ 25,000,000.0	$ 25,000,000.0	$ 25,000,000.0
Senior Debt [Member]
Accounting Policies [Line Items]
Debt instrument, face amount																			$ 100,000,000.0
Debt instrument, maturity date											Aug. 15, 2025
Interest rate (in hundredths)																			4.75%
McMahon Leasing [Member]
Accounting Policies [Line Items]
Goodwill	$ 263,000
Payments to Acquire Businesses, Gross	8,700,000
Finite-lived Intangible Assets Acquired	1,100,000
Internal Use Software [Member]
Accounting Policies [Line Items]
Estimated useful life											7 years
Total capitalized software costs			5,600,000				5,700,000				$ 5,600,000	5,700,000
Amortization of intangible assets											2,000,000.0	2,000,000.0	$ 2,400,000
Customer List Intangibles [Member]
Accounting Policies [Line Items]
Estimated useful life		10 years
Acquired finite lived intangible assets accumulated amortization			2,300,000				1,900,000				2,300,000	1,900,000
Amortization expense per year			340,000								340,000
Accumulated Amortization			2,442,000				2,044,000				2,442,000	2,044,000
Finite-Lived Intangible Assets, Gross			4,093,000				4,093,000				4,093,000	4,093,000
Amortization Expense Over Next Five Years											1,100,000
Finite-lived Intangible Assets Acquired		$ 3,400,000									$ 3,400,000	3,400,000
Purchase of lease receivables		$ 60,000,000.0
Customer List Intangibles [Member] | McMahon Leasing [Member]
Accounting Policies [Line Items]
Estimated useful life											12 years
Amortization expense per year			57,000								$ 57,000
Accumulated Amortization			172,000								172,000
Finite-Lived Intangible Assets, Gross	689,000
Amortization Expense Over Next Five Years											287,000
Trade Names [Member]
Accounting Policies [Line Items]
Finite-Lived Intangible Assets, Gross			135,000				135,000				135,000	135,000
Trade Names [Member] | McMahon Leasing [Member]
Accounting Policies [Line Items]
Finite-lived Intangible Assets Acquired	$ 135,000
Fair Value, Measurements, Recurring [Member]
Accounting Policies [Line Items]
Loans held for sale			589,143,000				$ 1,388,416,000				589,143,000	$ 1,388,416,000
Disposition Efforts, Reclassified [Member]
Accounting Policies [Line Items]
Loans held for investment						61,600,000
Other real estate owned			17,300,000			17,300,000					17,300,000
Commercial Portfolio Segment [Member] | Disposition Efforts, Reclassified [Member]
Accounting Policies [Line Items]
Net realized and unrealized gains (losses) on commercial loans, at fair value						3,500,000
Increase in allowance for credit losses						1,300,000
Provision for credit losses						3,500,000
Allowance for loan commitments						$ 2,200,000
Accounting Standards Update 2016-13 [Member]
Accounting Policies [Line Items]
Retained earnings																				$ 2,400,000
Deferred Tax Assets, Gross																				834,000
Allowance for credit losses																				2,600,000
Other liabilities																				(569,000)
Reserve on unfunded commitments																				$ 569,000
Accounting Standards Update 2020-04 [Member]
Accounting Policies [Line Items]
Notional Amount			6,800,000								6,800,000
Subordinated Debt			13,400,000								13,400,000
Securities Purchased From Previous Securitizations			12,600,000								12,600,000
Collateralized Loan Obligations And U.S. Government Agency Adjustable-Rate Mortgages Which Utilize LIBOR			335,400,000								335,400,000
U.S. Government Agencies With Adjustable Interest Rate Indices			58,500,000								58,500,000
Accounting Standards Update 2020-04 [Member] | Certain Financial Instruments Indexed To LIBOR [Member]
Accounting Policies [Line Items]
Loans			354,700,000,000								354,700,000,000
Accounting Standards Update 2020-04 [Member] | Student Loan [Member]
Accounting Policies [Line Items]
Loans			$ 8,500,000								$ 8,500,000